The Internet is one of the chief channels to reach business decision-makers, according to a new study conducted by Nielsen//NetRatings , MORI Research and The Washington Post Co.’s online unit.

The study, based on a survey of about 1,000 business decision-makers conducted by NetRatings’ @plan unit, MORI and washingtonpost.com, found that a majority — 60 percent — said the Web is the best way for advertisers to reach them. Magazines and newspapers followed at 55 percent and 45 percent respectively, while television came in just about 30 percent.

Almost 50 percent of the respondents said the Web has influenced them to make a purchasing decision for their business, while 35 percent said they had been influenced by magazines, and 20 percent by television. Seventy-seven percent said they considered Web the best channel through which to find out about new products and companies — more than twice as many as the next highest medium, magazines.

The study also found that increased usage of the Web by decision makers is leading directly to their decreased usage of leading traditional media. About a fifth of the respondents said they use the Web at least five hours per workday — excluding email use.

About 55 percent of the respondents said they had increased their Web usage during the past year. Half of those said they have decreased their television viewing as a result, while about 45 percent said they read fewer magazines or newspapers. An additional 40 percent of the survey’s respondents said they expect to increase their Web use during the next year.

About a third of the respondents came from organizations with more than 2,000 employees, while another third came from small businesses and startups, according to @Plan.

Still, some questions remain. For one thing, the study skews slightly toward the Internet-savvy — simply by dint of it being disseminated online, via the washingtonpost.com site. As a result, a greater number of respondents — about 18 percent — came from the high-tech and media industries than other sectors. Public-sector and educational decision-makers also comprised about 21 percent of the respondents.

In addition, the study found that while the majority of respondents said they preferred to receive new product advertisements via the Internet, they ranked television higher than the Internet in terms of having ads that they remember for “a long time,” 43 percent versus 17 percent. Fifty-four percent also agreed that television has interesting ads, while only 30 percent agreed that the Internet did as well.

And of course, washingtonpost.com has a vested interest in promoting its audiences and seeing online advertising in general do well.

Despite such caveats, the researchers say the study contributes to the growing body of evidence in favor of Web media — particularly news-type sites — as a sort of work-day “prime time,” during which high-income consumers and business buyers are best-reached via the Internet.

“The findings show that the Web, and particularly online news, has established itself as a powerful medium for reaching and influencing business decision makers,” said Carolyn Clark, Internet media analyst at Nielsen//NetRatings. “Not only are business decision-makers spending more time on the Internet when compared to other media, more than 60 percent recommended online advertising as a key marketing vehicle to reach them.”

That argument has been central to trade groups like the Online Publishers Association, in which washingtonpost.com is a participant. Members of the organization recently unveiled an ad network initiative designed to sell dayparts to advertisers looking to reach at-work audiences.

“The findings of this washingtonpost.com study provide further proof that online advertising is the best way for smart marketers to reach the most influential audiences,” said OPA Executive Director Michael Zimbalist. “Their usage is concentrated during the daytime, while they are at work and undistracted by other media choices.”

Earlier this year, the OPA commissioned a study indicating that concluded that the Internet was the dominant medium during the workday, and second only after work to television.